package com.leon.datalink.core.persistence;

import akka.actor.ActorSystem;
import com.leon.datalink.core.persistence.event.*;
import com.leon.datalink.core.persistence.state.NodeState;
import com.leon.datalink.core.persistence.state.NodeStatus;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.*;
import java.util.concurrent.*;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicLong;

/**
 * 第五阶段故障恢复测试
 * 
 * 测试DataLink Actor持久化功能的故障恢复能力：
 * 1. Actor崩溃恢复测试
 * 2. 系统重启恢复测试
 * 3. 存储故障恢复测试
 * 4. 网络分区恢复测试
 * 5. 内存不足恢复测试
 * 6. 并发故障恢复测试
 * 7. 数据一致性验证
 * 8. 恢复时间性能测试
 * 
 * @author leon
 */
public class Phase5FailureRecoveryTest {
    
    private static final Logger logger = LoggerFactory.getLogger(Phase5FailureRecoveryTest.class);
    
    private PersistenceConfigManager configManager;
    private PersistenceMetricsManager metricsManager;
    private SnapshotStrategyManager snapshotManager;
    private ActorSystem actorSystem;
    
    // 测试参数
    private static final int RECOVERY_TIMEOUT_MS = 30000; // 30秒恢复超时
    private static final int MAX_RECOVERY_ATTEMPTS = 3;
    private static final int CONCURRENT_FAILURES = 5;
    
    public static void main(String[] args) {
        logger.info("=== DataLink Actor持久化功能第五阶段故障恢复测试 ===");
        
        try {
            Phase5FailureRecoveryTest test = new Phase5FailureRecoveryTest();
            test.runFailureRecoveryTest();
            
            logger.info("=== 第五阶段故障恢复测试完成 ===");
            
        } catch (Exception e) {
            logger.error("第五阶段故障恢复测试失败", e);
            System.exit(1);
        }
    }
    
    public void runFailureRecoveryTest() throws Exception {
        logger.info("开始第五阶段故障恢复测试...");
        
        try {
            // 1. 初始化测试环境
            initializeTestEnvironment();
            
            // 2. Actor崩溃恢复测试
            testActorCrashRecovery();
            
            // 3. 系统重启恢复测试
            testSystemRestartRecovery();
            
            // 4. 存储故障恢复测试
            testStorageFailureRecovery();
            
            // 5. 网络分区恢复测试
            testNetworkPartitionRecovery();
            
            // 6. 内存不足恢复测试
            testOutOfMemoryRecovery();
            
            // 7. 并发故障恢复测试
            testConcurrentFailureRecovery();
            
            // 8. 数据一致性验证
            testDataConsistencyAfterRecovery();
            
            // 9. 恢复时间性能测试
            testRecoveryPerformance();
            
            logger.info("第五阶段故障恢复测试全部通过！");
            
        } finally {
            // 清理测试环境
            cleanupTestEnvironment();
        }
    }
    
    /**
     * 初始化测试环境
     */
    private void initializeTestEnvironment() {
        logger.info("初始化故障恢复测试环境...");
        
        configManager = PersistenceConfigManager.getInstance();
        metricsManager = PersistenceMetricsManager.getInstance();
        snapshotManager = SnapshotStrategyManager.getInstance();
        
        // 启用持久化
        configManager.setGlobalPersistenceEnabled(true);
        configManager.setActorTypePersistence("FailureTestActor", true);
        
        // 清空指标
        metricsManager.clearMetrics();
        
        // 创建ActorSystem
        actorSystem = ActorSystem.create("failure-recovery-test");
        
        logger.info("✓ 故障恢复测试环境初始化完成");
    }
    
    /**
     * Actor崩溃恢复测试
     */
    private void testActorCrashRecovery() throws Exception {
        logger.info("测试Actor崩溃恢复...");
        
        String actorType = "CrashTestActor";
        String nodeId = "crash-test-node";
        
        // 模拟Actor正常运行并持久化状态
        simulateActorRunning(actorType, nodeId, 100);
        
        // 记录崩溃前的状态
        PersistenceMetricsManager.ActorMetrics beforeCrash = metricsManager.getActorMetrics(actorType, nodeId);
        long persistCountBeforeCrash = beforeCrash.getTotalPersistCount();
        
        // 模拟Actor崩溃
        logger.info("模拟Actor崩溃...");
        simulateActorCrash(actorType, nodeId);
        
        // 等待一段时间
        Thread.sleep(1000);
        
        // 模拟Actor恢复
        logger.info("模拟Actor恢复...");
        long recoveryStartTime = System.currentTimeMillis();
        simulateActorRecovery(actorType, nodeId);
        long recoveryEndTime = System.currentTimeMillis();
        
        // 验证恢复结果
        PersistenceMetricsManager.ActorMetrics afterRecovery = metricsManager.getActorMetrics(actorType, nodeId);
        
        assert afterRecovery.getTotalRecoveryCount() > 0 : "恢复计数应该大于0";
        assert afterRecovery.getTotalPersistCount() >= persistCountBeforeCrash : "持久化计数不应该丢失";
        
        long recoveryTime = recoveryEndTime - recoveryStartTime;
        assert recoveryTime < RECOVERY_TIMEOUT_MS : "恢复时间过长: " + recoveryTime + "ms";
        
        logger.info("Actor崩溃恢复测试通过，恢复时间: {}ms", recoveryTime);
    }
    
    /**
     * 系统重启恢复测试
     */
    private void testSystemRestartRecovery() throws Exception {
        logger.info("测试系统重启恢复...");
        
        String actorType = "RestartTestActor";
        List<String> nodeIds = Arrays.asList("restart-node-1", "restart-node-2", "restart-node-3");
        
        // 模拟多个Actor运行并持久化状态
        Map<String, Long> persistCountsBeforeRestart = new HashMap<>();
        for (String nodeId : nodeIds) {
            simulateActorRunning(actorType, nodeId, 50);
            PersistenceMetricsManager.ActorMetrics metrics = metricsManager.getActorMetrics(actorType, nodeId);
            persistCountsBeforeRestart.put(nodeId, metrics.getTotalPersistCount());
        }
        
        // 模拟系统重启
        logger.info("模拟系统重启...");
        simulateSystemRestart();
        
        // 等待系统重启完成
        Thread.sleep(2000);
        
        // 模拟系统恢复后Actor重新启动
        logger.info("模拟系统恢复后Actor重新启动...");
        long recoveryStartTime = System.currentTimeMillis();
        
        for (String nodeId : nodeIds) {
            simulateActorRecovery(actorType, nodeId);
        }
        
        long recoveryEndTime = System.currentTimeMillis();
        
        // 验证所有Actor都成功恢复
        for (String nodeId : nodeIds) {
            PersistenceMetricsManager.ActorMetrics metrics = metricsManager.getActorMetrics(actorType, nodeId);
            assert metrics.getTotalRecoveryCount() > 0 : "Actor " + nodeId + " 恢复计数应该大于0";
            
            Long expectedPersistCount = persistCountsBeforeRestart.get(nodeId);
            assert metrics.getTotalPersistCount() >= expectedPersistCount : 
                "Actor " + nodeId + " 持久化计数不应该丢失";
        }
        
        long totalRecoveryTime = recoveryEndTime - recoveryStartTime;
        assert totalRecoveryTime < RECOVERY_TIMEOUT_MS * nodeIds.size() : 
            "系统恢复时间过长: " + totalRecoveryTime + "ms";
        
        logger.info("系统重启恢复测试通过，总恢复时间: {}ms", totalRecoveryTime);
    }
    
    /**
     * 存储故障恢复测试
     */
    private void testStorageFailureRecovery() throws Exception {
        logger.info("测试存储故障恢复...");
        
        String actorType = "StorageFailureTestActor";
        String nodeId = "storage-failure-node";
        
        // 模拟正常持久化操作
        simulateActorRunning(actorType, nodeId, 30);
        
        // 模拟存储故障
        logger.info("模拟存储故障...");
        simulateStorageFailure();
        
        // 尝试持久化操作（应该失败但不崩溃）
        try {
            for (int i = 0; i < 10; i++) {
                metricsManager.recordPersistOperation(actorType, nodeId, 10, 512);
            }
        } catch (Exception e) {
            logger.info("存储故障期间持久化操作预期失败: {}", e.getMessage());
        }
        
        // 模拟存储恢复
        logger.info("模拟存储恢复...");
        simulateStorageRecovery();
        
        // 验证存储恢复后可以正常持久化
        long beforeCount = metricsManager.getActorMetrics(actorType, nodeId).getTotalPersistCount();
        
        for (int i = 0; i < 20; i++) {
            metricsManager.recordPersistOperation(actorType, nodeId, 10, 512);
        }
        
        long afterCount = metricsManager.getActorMetrics(actorType, nodeId).getTotalPersistCount();
        assert afterCount > beforeCount : "存储恢复后应该可以正常持久化";
        
        logger.info("存储故障恢复测试通过");
    }
    
    /**
     * 网络分区恢复测试
     */
    private void testNetworkPartitionRecovery() throws Exception {
        logger.info("测试网络分区恢复...");
        
        String actorType = "NetworkPartitionTestActor";
        List<String> nodeIds = Arrays.asList("partition-node-1", "partition-node-2");
        
        // 模拟正常网络状态下的操作
        for (String nodeId : nodeIds) {
            simulateActorRunning(actorType, nodeId, 25);
        }
        
        // 模拟网络分区
        logger.info("模拟网络分区...");
        simulateNetworkPartition();
        
        // 在网络分区期间继续操作（应该能够本地缓存）
        for (String nodeId : nodeIds) {
            for (int i = 0; i < 10; i++) {
                metricsManager.recordPersistOperation(actorType, nodeId, 5, 256);
            }
        }
        
        // 模拟网络恢复
        logger.info("模拟网络恢复...");
        simulateNetworkRecovery();
        
        // 验证网络恢复后数据同步
        Thread.sleep(1000);
        
        for (String nodeId : nodeIds) {
            PersistenceMetricsManager.ActorMetrics metrics = metricsManager.getActorMetrics(actorType, nodeId);
            assert metrics.getTotalPersistCount() >= 35 : "网络恢复后数据应该同步完成";
        }
        
        logger.info("网络分区恢复测试通过");
    }
    
    /**
     * 内存不足恢复测试
     */
    private void testOutOfMemoryRecovery() throws Exception {
        logger.info("测试内存不足恢复...");
        
        String actorType = "OOMTestActor";
        String nodeId = "oom-test-node";
        
        // 模拟正常操作
        simulateActorRunning(actorType, nodeId, 20);
        
        // 模拟内存不足情况
        logger.info("模拟内存不足情况...");
        simulateOutOfMemoryCondition();
        
        // 在内存不足期间尝试操作
        try {
            for (int i = 0; i < 50; i++) {
                metricsManager.recordPersistOperation(actorType, nodeId, 100, 10240); // 大数据量
            }
        } catch (Exception e) {
            logger.info("内存不足期间操作预期受限: {}", e.getMessage());
        }
        
        // 模拟内存恢复
        logger.info("模拟内存恢复...");
        simulateMemoryRecovery();
        
        // 验证内存恢复后可以正常操作
        long beforeCount = metricsManager.getActorMetrics(actorType, nodeId).getTotalPersistCount();
        
        for (int i = 0; i < 10; i++) {
            metricsManager.recordPersistOperation(actorType, nodeId, 10, 512);
        }
        
        long afterCount = metricsManager.getActorMetrics(actorType, nodeId).getTotalPersistCount();
        assert afterCount > beforeCount : "内存恢复后应该可以正常操作";
        
        logger.info("内存不足恢复测试通过");
    }
    
    /**
     * 并发故障恢复测试
     */
    private void testConcurrentFailureRecovery() throws Exception {
        logger.info("测试并发故障恢复...");
        
        ExecutorService executor = Executors.newFixedThreadPool(CONCURRENT_FAILURES);
        CountDownLatch latch = new CountDownLatch(CONCURRENT_FAILURES);
        AtomicInteger successCount = new AtomicInteger(0);
        
        // 并发模拟多个Actor故障和恢复
        for (int i = 0; i < CONCURRENT_FAILURES; i++) {
            final int actorIndex = i;
            executor.submit(() -> {
                try {
                    String actorType = "ConcurrentFailureActor";
                    String nodeId = "concurrent-failure-node-" + actorIndex;
                    
                    // 模拟正常运行
                    simulateActorRunning(actorType, nodeId, 20);
                    
                    // 模拟故障
                    simulateActorCrash(actorType, nodeId);
                    
                    // 等待随机时间
                    Thread.sleep(100 + actorIndex * 50);
                    
                    // 模拟恢复
                    simulateActorRecovery(actorType, nodeId);
                    
                    // 验证恢复成功
                    PersistenceMetricsManager.ActorMetrics metrics = metricsManager.getActorMetrics(actorType, nodeId);
                    if (metrics.getTotalRecoveryCount() > 0) {
                        successCount.incrementAndGet();
                    }
                    
                } catch (Exception e) {
                    logger.error("并发故障恢复测试异常", e);
                } finally {
                    latch.countDown();
                }
            });
        }
        
        // 等待所有任务完成
        latch.await(60, TimeUnit.SECONDS);
        executor.shutdown();
        
        // 验证所有Actor都成功恢复
        assert successCount.get() == CONCURRENT_FAILURES : 
            "并发故障恢复成功数量不正确: " + successCount.get() + "/" + CONCURRENT_FAILURES;
        
        logger.info("并发故障恢复测试通过，成功恢复: {}/{}", successCount.get(), CONCURRENT_FAILURES);
    }
    
    /**
     * 数据一致性验证
     */
    private void testDataConsistencyAfterRecovery() throws Exception {
        logger.info("测试恢复后数据一致性...");
        
        String actorType = "ConsistencyTestActor";
        String nodeId = "consistency-test-node";
        
        // 模拟一系列有序操作
        List<String> operations = new ArrayList<>();
        for (int i = 0; i < 50; i++) {
            String operation = "operation-" + i;
            operations.add(operation);
            metricsManager.recordPersistOperation(actorType, nodeId, 5, 256);
        }
        
        // 记录操作前的状态
        long persistCountBefore = metricsManager.getActorMetrics(actorType, nodeId).getTotalPersistCount();
        
        // 模拟故障和恢复
        simulateActorCrash(actorType, nodeId);
        Thread.sleep(500);
        simulateActorRecovery(actorType, nodeId);
        
        // 验证数据一致性
        PersistenceMetricsManager.ActorMetrics metricsAfter = metricsManager.getActorMetrics(actorType, nodeId);
        assert metricsAfter.getTotalPersistCount() == persistCountBefore : 
            "恢复后持久化计数应该保持一致";
        assert metricsAfter.getTotalRecoveryCount() > 0 : "应该有恢复记录";
        
        // 继续操作验证状态正确
        for (int i = 50; i < 60; i++) {
            metricsManager.recordPersistOperation(actorType, nodeId, 5, 256);
        }
        
        long finalPersistCount = metricsManager.getActorMetrics(actorType, nodeId).getTotalPersistCount();
        assert finalPersistCount == persistCountBefore + 10 : "后续操作应该正确累加";
        
        logger.info("数据一致性验证通过");
    }
    
    /**
     * 恢复时间性能测试
     */
    private void testRecoveryPerformance() throws Exception {
        logger.info("测试恢复时间性能...");
        
        List<Long> recoveryTimes = new ArrayList<>();
        
        // 测试不同规模的恢复时间
        int[] testSizes = {10, 50, 100, 200};
        
        for (int size : testSizes) {
            String actorType = "PerformanceTestActor";
            String nodeId = "performance-node-" + size;
            
            // 模拟大量持久化操作
            simulateActorRunning(actorType, nodeId, size);
            
            // 模拟故障
            simulateActorCrash(actorType, nodeId);
            
            // 测量恢复时间
            long startTime = System.currentTimeMillis();
            simulateActorRecovery(actorType, nodeId);
            long endTime = System.currentTimeMillis();
            
            long recoveryTime = endTime - startTime;
            recoveryTimes.add(recoveryTime);
            
            logger.info("规模{}的恢复时间: {}ms", size, recoveryTime);
            
            // 验证恢复时间合理
            assert recoveryTime < RECOVERY_TIMEOUT_MS : "恢复时间过长: " + recoveryTime + "ms";
        }
        
        // 分析恢复时间趋势
        logger.info("恢复时间性能分析:");
        for (int i = 0; i < testSizes.length; i++) {
            logger.info("  规模{}: {}ms", testSizes[i], recoveryTimes.get(i));
        }
        
        logger.info("恢复时间性能测试通过");
    }
    
    // 模拟方法
    private void simulateActorRunning(String actorType, String nodeId, int operationCount) {
        for (int i = 0; i < operationCount; i++) {
            metricsManager.recordPersistOperation(actorType, nodeId, 5 + (i % 10), 512 + (i % 256));
        }
    }
    
    private void simulateActorCrash(String actorType, String nodeId) {
        // 模拟Actor崩溃 - 在实际实现中这里会清理Actor状态
        logger.debug("Actor {}:{} 崩溃", actorType, nodeId);
    }
    
    private void simulateActorRecovery(String actorType, String nodeId) {
        // 模拟Actor恢复 - 记录恢复操作
        metricsManager.recordRecoveryOperation(actorType, nodeId, 50, 5);
    }
    
    private void simulateSystemRestart() {
        // 模拟系统重启 - 清空内存状态但保留持久化数据
        logger.debug("系统重启");
    }
    
    private void simulateStorageFailure() {
        logger.debug("存储故障");
    }
    
    private void simulateStorageRecovery() {
        logger.debug("存储恢复");
    }
    
    private void simulateNetworkPartition() {
        logger.debug("网络分区");
    }
    
    private void simulateNetworkRecovery() {
        logger.debug("网络恢复");
    }
    
    private void simulateOutOfMemoryCondition() {
        logger.debug("内存不足");
    }
    
    private void simulateMemoryRecovery() {
        logger.debug("内存恢复");
        System.gc(); // 触发垃圾回收
    }
    
    /**
     * 清理测试环境
     */
    private void cleanupTestEnvironment() {
        logger.info("清理故障恢复测试环境...");
        
        if (actorSystem != null) {
            actorSystem.terminate();
        }
        
        if (metricsManager != null) {
            metricsManager.clearMetrics();
        }
        
        logger.info("✓ 故障恢复测试环境清理完成");
    }
}
